Simulation of Preprinted Forms

ABSTRACT

In one embodiment, a method for the simulation of preprinted forms is disclosed. The method includes receiving a first image as a back drop of a form, the image including a plurality of printable features corresponding to positions of the image. A second image is received as data to be filled in to the form, the second image including a second plurality of printable features corresponding to positions of the image, wherein the second plurality of printable features each have an assigned ink transparency. A feature of the first image is blended with a corresponding feature of the second image based on the assigned ink transparencies to form a blended feature. The blended features are combined to form a blended image that blends the first and the second images and is suitable for printing.

The present patent application is a Continuation application claimingpriority from application Ser. No. 14/172,820, filed Feb. 4, 2014, whichis currently pending.

FIELD OF THE INVENTION

The invention relates to the field of image reproduction, and inparticular, to combining data with preprinted forms.

BACKGROUND

Printers are common peripheral devices attached to computers. A printerallows a computer user to make a hard copy of documents that are createdin a variety of applications and programs on a computer. To functionproperly, a channel of communication is established (e.g., via a networkconnection) between the printer and the computer to enable the printerto receive commands and information from the host computer. Once aconnection is established between a computer and the printer, printingsoftware is implemented at a print server to manage a print job throughthe complete printing process.

Often, print jobs are produced by printing data on a document thatalready has a preprinted form. The form may include text, graphics,gridlines, and images together with logos or branding. However,preprinted forms are expensive to create and handle. In particular,printer users struggle with the cost and logistics of specifying,purchasing, storing, moving and controlling large volumes of preprintedforms. Waste occurs when forms are modified and the remaining stock ofthe old version is eliminated.

The customer environment becomes more efficient and lower cost ifpreprinted forms are eliminated by substituting blank stock. The formpart of the print job is represented as overlay data and the fill-indata for the form is overlaid on the form.

Accordingly, an approach to accurately represent and print document dataagainst a background of form data is desired.

SUMMARY

In one embodiment, a method for the simulation of preprinted forms isdisclosed. The method includes receiving a first image as a backgroundof a form, the image including a plurality of printable featurescorresponding to positions of the image. A second image is received asdata to be filled in to the form, the second image including a secondplurality of printable features corresponding to positions of the image,wherein the second plurality of printable features each have an assignedink transparency. A feature of the first image is blended with acorresponding feature of the second image based on the assigned inktransparencies to form a blended feature. The blended features arecombined to form a blended image that blends the first and the secondimages and is suitable for printing.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the present invention can be obtained from thefollowing detailed description in conjunction with the followingdrawings, in which:

FIG. 1 illustrates one embodiment of a printing network;

FIG. 2 illustrates one embodiment of a print controller;

FIG. 3 illustrates one embodiment of a process flow diagram of combiningcolors of form data;

FIG. 4 illustrates one embodiment of a process flow diagram of combininginks; and

FIG. 5 illustrates one embodiment of a computer system.

DETAILED DESCRIPTION

It is possible to represent a completed form using knockout. When thedata overlaps the form, then the color of the simulated preprinted formis “knocked out” and replaced with a color from the document data.Knockout can be improved by simply excluding white and the color of theprinting medium (e.g. paper) to be excluded from knockout. Even whensome colors are excluded from knockout, the final combined form anddocument data may be rendered inaccurately on the printed paper.Knockout does not provide any mixing of overlapping colors.

Better results may be obtained by explicitly simulating overlaying lightcolors on a dark preprinted form. Better results are also obtained byblending overprinted values with the underlying simulated preprintedform color. For example, a blue semitransparent ink written over ayellow preprinted form results in a greenish color. A knockout approachhowever will present only the blue ink color. The greenish result is amore accurate duplication of the original result that would be achievedusing a preprinted form. As described below these results may beobtained by hardware or an efficient software algorithm. There is nooverhead on existing printing code to create transparent regions orcreate a metadata mapping on the user data as layer upon layer is added.As described below the user data typically uses overpaint blending ruleswhich must be mixed in with transparency blending rules.

Reference in the specification to “one embodiment” or “an embodiment”means that a particular feature, structure, or characteristic describedin connection with the embodiment is included in at least one embodimentof the invention. The appearances of the phrase “in one embodiment” invarious places in the specification are not necessarily all referring tothe same embodiment.

FIG. 1 is a block diagram illustrating a printing network 100. Network100 includes a host system 110 in communication with a printing system130 to print a sheet image 120 onto a print medium 180 (e.g., paper) viaa printer 160. The resulting print medium 180 may be printed in colorand/or in any of a number of gray shades, including black and white.

The host system 110 may include any computing device, such as a personalcomputer, a server, or even a digital imaging device, such as a digitalcamera or a scanner. The sheet image 120 may be any file or data thatdescribes how an image on a sheet of print medium should be printed. Forexample, the sheet image 120 may include PostScript data, PrinterCommand Language (PCL) data, and/or any other printer language data. Theprint controller 140 processes the sheet image to generate a bitmap 150for printing to the print medium 180 via the printer 160.

The printing system 130 may be a high-speed printer operable to printrelatively high volumes (e.g., greater than 100 pages per minute). Theprint medium 180 may be continuous form paper, cut sheet paper, and/orany other tangible medium suitable for printing. In one embodiment, theprinting system 130 includes the printer 160 that presents the bitmap150 onto the print medium 180 (e.g., via toner, ink, etc.) based on thesheet image 120.

The print controller 140 may be any system, device, software, circuitryand/or other suitable component operable to transform the sheet image120 for generating the bitmap 150 in accordance with printing onto theprint medium 180. FIG. 2 is a block diagram illustrating an exemplaryprint controller 140.

Referring to FIG. 2, the print controller 140, in its generalized form,includes an interpreter module 212 and a halftoning module 214. In oneembodiment, these separate components represent hardware used toimplement the print controller 140. Alternatively or additionally, thecomponents may represent logical blocks implemented by executingsoftware instructions in a processor of the printer controller 140.Accordingly, the invention is not intended to be limited to anyparticular implementation as such may be a matter of design choice.

The interpreter module 212 is operable to interpret, render, rasterize,or otherwise convert images (i.e., raw sheetside images such as sheetimage 120) of a print job into sheetside bitmaps. The sheetside bitmapsgenerated by the interpreter module 212 are each a two-dimensional arrayof pixels representing an image of the print job e.g., a continuous toneimage (CTI), or contone image also referred to as full sheetsidebitmaps.

The two-dimensional pixel arrays are considered “full” sheetside bitmapsbecause the bitmaps include the entire set of pixels for the image. Theinterpreter module 212 is operable to interpret or render multiple rawsheetsides concurrently so that the rate of rendering substantiallymatches the rate of imaging of production print engines.

The halftoning module 214 is operable to represent the sheetside bitmapsas patterns of ink drops or other dots, having one or more differentdrop or dot sizes. For example, the halftoning module 214 may convertthe continuous tone sheetside bitmaps to a pattern of ink drops forapplication to the print medium 180 (e.g., paper). Once computed, thehalftoning module 214 transfers the converted sheetside bitmaps to theprint head controllers of the printer 160 to apply the ink drop(s) tothe tangible medium 180. Instead of halftoning, other types of modulesmay be used to prepare the image for printing on other types ofprinters. The module may convert the image to a binary, multi-bit,single color or multi-tone image.

Before halftoning, the two images, the background from the preprintedform and the fill-in data to be printed over the form are combined. Anoptional tiling module 216 divides the bit maps of both images intotiles. This reduces the complexity of the combination. An ink blendingmodule 218 combines the images for each tile based on the color value ofboth images and the transparency assigned to the two colors, asexplained in more detail below. The tiles are combined together again inthe tiling modules and then the halftoning module prepares the combinedimage for printing. If there is no tiling module, then the images arecombined and halftoned as bitmaps.

As described below, the preprinted form's background data is blendedinto the page-specific fill-in data using a transparency setting for thefill-in-data (per plane) to simulate the opacity of inks or toners thatmight have been used to generate the fill-in data. First, the backgroundof the preprinted form is simulated. Then the effect of printing thefill-in data over the background of the form is simulated. If, forexample, the background of the form is a yellow background and somecolor is printed on top of it, then the results will vary. Iftransparent inks are used, then the resulting color will be differentfrom the same ink color over black or white. The resulting color of thefill-in data on the print medium is affected by the form itself.

To accurately represent the effect, the properties of the ink beingsimulated can be accounted for. Different inks have differenttransparency properties. Some inks have almost no transparency and thecolor of the ink will not be affected by the backdrop. Other inks havehigh transparency so that e.g. yellow fill-in data over a bluebackground form region results in a green appearance.

In the case of a workflow that uses preprinted forms and fills them inusing a particular kind of printer, the output will have a finalfinished look that depends on the papers and inks that are used. Thisworkflow can be matched using electronic forms that are printed togetherwith the filled in form data, by accurately characterizing the inks. Tomake the appearance of the electronically stored forms resemble that ofthe preprinted forms, the nature of the inks used in the print enginemay be considered. A blending that simulates the printer inks can occurso that the results are about the same for both types of documentproduction.

FIG. 3 is a process flow diagram of combining colors of page-specificfill-in data with colors of a simulated preprinted form. At 310 a firstside map is generated based on the fill-in data that would be printedover a preprinted form. At 320 this side map is divided into tiles. At330 a second side map is also created based on a representation of thepreprinted form. At 340, this side map is divided into tiles. The tilingmay be performed in any of a variety of ways, depending on theparticular implementation.

The tile types are then mixed. This can be done in a variety of ways.One way to mix tile types is as follows:

Solids are blended with solids, rectangles, and text by adjustingcolors;

Rectangles are blended with solids by adjusting colors;

Text is blended with solids by adjusting colors; and

Other combinations are rendered into the first side map.

These blending formulas all tend toward “darker” results in each plane.The color values can only increase based on the transparency of thesimulated inks. A completely transparent ink does not increase thebackground color unless the foreground color value is greater than thebackground color value. A completely opaque ink does not decrease thebackground color. In the examples below, the inks are not treated aspaints. With paint, an opaque color (such as white) may be able tocompletely cover a color underneath. Expressed as ink printing values,the values for the top color would completely remove the backgroundvalues. If treated as paints, only a fully transparent ink would achievean effect that is somewhat realistic, meaning the effect of printingover a preprinted form.

Considering the two side maps in more detail, two bitmaps are created at310, and 330, one for the original page-specific fill-in data and onefor the preprinted form. Using a transparency value describing theopacity or transparency of the printer inks or toner that are to besimulated, the preprinted form bitmap may be blended into the clientdata bitmap to add the preprinted background. In other words, theoperations at 320 and 340 are optional.

Instead of the bitmap, tiles may be used. When tiles are used, theblending is performed in a similar way but each tile is blended as awhole rather than bit-wise. This may greatly reduce the number ofblending operation calculations. The blending, whether bit-wise or withtiles, can be expressed mathematically. The blending operations can beperformed in black and white or for color documents in any of a varietyof different color planes. For CMYK printing, four color planes can beused, one for each of the four components CMYK. Alternatively, only twoor three color planes can be used. The color planes are then combinedfor the final output. Similar operations may be used for other colortypes of color spaces, including hexachrome and DeviceN.

For the equations below X0 is the value of the color of a tile for thefirst side map corresponding to the background form data. X1 is thevalue of the color of the same tile for the second side mapcorresponding to the page-specific fill-in data. Xn is the value of thecolor that is to be printed. For 8-bit color systems, these values willrange between 0 and 255, but the values in these equations is normalizedbetween 0.0 and 1.0. Mi is the transparency or opacity of the fill-indata. The Mi values in the example below are between 0.0 for opaque and1.0 for transparent, but the approach may be modified to suit differentnumerical scales for Mi.

For normal blending, the new color value per color plane, where nrepresents one of e.g. four color planes, CMYK, is given as follows:

Xn=1−((1−X0)*(1−X1)), where the ink opacity is ignored

For a preprinted form simulation, let X0 be the final colorant (of theoverlay in the bitmap) and X1 be the color value of the data filled into the form. Let Xmax=1.0, then for ink opacity Mi (for the givencolorant), the following relations may be used:

For Mi=1 (transparent ink), Xn=max(X0,X1)

For Mi=0 (opaque ink), Xn=min(Xmax,X0+X1)

For 0<Mi<1 (real ink), Xn=min(Xmax,max(X0,X1)+(1−Mi)*min(X0,X1))

As described above, the different colors are blended based ontransparency values for the inks that are being simulated. These valuesare adapted for the inks that will be used to print the blended finaldocument. The transparency setting blends in the final color values andtransparency with the background's color values. The fill-in data'stransparency is adjusted by a percentage that describes the transparencyor opacity of the toner or ink being simulated for the data. Byadjusting the transparency values, different print technologies can besimulated.

After the color value for each tile is determined. The tiles arecombined at 360 to form a final combined image. The image combines thecolors for each tile and simulates printing the fill-in data over apreprinted form. The combined image may then be printed at 370.

The combination of inks at 350 is shown in more detail in the processflow diagram of FIG. 4. At 410 the two side maps are each divided intoseparate component images for each color plane. For a CMYK color plane,there will be a C image, an M image, a Y image, and a K image for bothside maps. At 420, the blending starts for the first color component,for example, the C component. As described herein the color values foreach of the four color planes are blended, however, the invention is notso limited. In order to reduce computational complexity blending may bedone for only some of the color planes. Since the eye is more sensitiveto variations in Cyan and Yellow, these two colors may be blended andnot Magenta and Black. Alternatively only Cyan is blended. For the othercolors, e.g. magenta and black, a simpler addition of the two values ora knockout approach may be used.

At 420, the value for first color component of the first printablefeature of the first image and the value of the first color component ofthe corresponding printable feature of the second image are accessed. At430, the color components, also referred to as the saturationcomponents, are compared. At 440, the smaller of the two colorcomponents is scaled and added to the full value of the larger of thetwo color components. At 450, the sum of the two values is taken as thecolor component value for the output image. As mentioned above, thefinal color component may be limited to some maximum value. For asaturation scale from 0 to 1, the maximum value is 1. If the sum isgreater than 1, then the final value for the color component of theprintable feature will be 1.

This process is repeated at 460 for each printable feature and at 470for each color component. The sums at 450 may be combined into tiles orcombined to form bitmaps. The tiles may be combined at 460 using any ofa variety of different approaches. Adjustment may be made to the colorvalues as the tiles are recombined depending on the particularimplementation.

Ink transparency may be determined in any of a variety of differentways. Different measurement systems may be used for different ink andprinter types. For best results each colorant (cyan, magenta, yellow,and black) will each have its own Mi value determined using the realinks. This can be measured for a particular ink formula and printercombination and then the values may be used by the print controller asdescribed in the context of FIG. 3.

In one example, to measure ink transparency, the ink is printed onto acolorfast surface that will not change when it becomes wet with anapplied ink, as in a real preprinted form. For example, the form canhave 25% density in C, M, Y, and K. Printing various levels of cyan onboth the cyan part of the form and the white part should allow a basicdensitometer to measure the resultant densities and calculate the inkopacity by using the measured results and solving the equations for Mi.

For example, using a 25% background (X0) and 70% foreground (X1) of oneof the colorants, and measuring the combination (Xn) at 80%, provides:

Mi=(X1+X0−Xn)/X0=0.6

The non-linear nature of the equations as the densities get higher makesMi approach 1.0, (for example, when X1 and Xn=1.0, Mi becomes X0/X0, or1.0 for all backgrounds). The equations become very non-linear if thecalculations require using Xmax (1.0), for example. For lower values,(for example, with X1 about the same as X0 and where Xn measures about2X1), we get Mi closer to 0. It will usually be true from themeasurements that Xn will be less than the value of X1+X0 while alsogreater than either X1 or X0 individually, so the numerator should bepositive. Also, as X0 approaches 0, X1 should be almost the same as Xn,but it is difficult to find a factor mathematically using X0=0.

The equation above may be applied to each colorant (i.e. each ink color)in the same manner. Alternatively, the equation may be applied only tothe more important colors, such as cyan first, then magenta.

In the test chart printing described above, uncombined colorants areprinted so that the form's colorants are unaltered. This is to allow thesystem to be calibrated for a particular type of ink. However, thenature of the ink may not allow a consistent measurement of opacitygiven all preprinted densities mixed with all overlaying densities. Inthis case, approximations may be used for the most important parts ofthe document. As an example, a form designed to have a light background(like a bank check) overlaid with a darker ink can be used to explicitlymeasure the desired mixing. In other words, a portion of a document inwhich the text is printed over the background can be printed as a testsample. Ink systems are not very linear so other areas won't look thesame on such a simulation if the same parameters are used, but this doespermit the critical portion to be effectively simulated.

While the above formulas may be used to directly calculate anappropriate amount for each ink colorant. A table look up may be moreaccurate and faster in a real system. Color mixing tables may be usedlook up resultant values from a sparse table of colorant fill-in andbackground feature mixtures. Intermediate values may be interpolated.Interpolation techniques established for color management profiles maybe used to provide more accuracy if desired. A set of 4 one-dimensionaltables one for each colorant can be created to create a mixing curve.Points in between points on the table may be determined by linearinterpolation. A four-dimensional mixing table that includes allcolorants together will allow simulation of colorant interactions foreven more accuracy. The calculation and determination of ink levels andthe degree of accuracy may be adapted to suit different implementationsincluding print speed demands and available processing resources.

The density of many inks is affected by the thickness of the ink layer.Thicker ink is less transparent. At the maximum thickness for aparticular printer, the densitometer reading may be greater than 1.0.Any ink transparency value or ink combination table may consider printedink thickness and base the values on an average thickness at which theprinter typically operates.

As mentioned above, the sheet side images may be broken into tiles tomake calculations simpler and to reduce the demands on memory forblending images. Smaller tiles require less memory to process and canlater be recombined to generate the complete sheet side image. The tilesmay be made still more efficient by using meta-data structures torepresent the content of corresponding portions of a bitmap memory. Themetadata structures represent the bitmap in a compact form withoutrequiring writing of the pixels of a data object to the bitmap memory.

A compressed bitmap may then be generated from the meta-data structures.Data is read from the bitmap only where the meta-data cannot compactlyrepresent the content of the corresponding portion of the bitmap memory.

The tiling may be done in a variety of different ways. In someembodiments, a compressed bitmap representation of a sheet side image isgenerated with a meta-data structure for each of a number of portions ofthe bitmap meta data. The portion can be defined by bounding boxes of aparticular size. The metadata stores information about data object inthe bitmap such as rectangle, transparency masks, palettes, images, etc.

Data objects in the bitmap are identified and the correspondingmeta-data structure is updated for any corresponding portions of thebitmap that would be affected if data derived from the data object wereto be written in the bitmap memory. A corresponding data field type ineach meta-data structure is also updated. A bitmap representation of thesheet side image may then be compressed by excluding the data objectsthat are contained in the meta data structure.

The blending operations may be performed on the data objects for the twosheet side images. The data objects may then be combined and the newsheet side image built using the combined metadata.

FIG. 5 illustrates a computer system 1100 on which print controller 140and/or host system 110 may be implemented. Computer system 1100 includesa system bus 1120 for communicating information, and a processor 1110coupled to bus 1120 for processing information.

Computer system 1100 further comprises a random access memory (RAM) orother dynamic storage device 1125 (referred to herein as main memory),coupled to bus 1120 for storing information and instructions to beexecuted by processor 1110. Main memory 1125 also may be used forstoring temporary variables or other intermediate information duringexecution of instructions by processor 1110. Computer system 1100 alsomay include a read only memory (ROM) and or other static storage device1126 coupled to bus 1120 for storing static information and instructionsused by processor 1110.

A data storage device 1127 such as a magnetic disk or optical disc andits corresponding drive may also be coupled to computer system 1100 forstoring information and instructions. Computer system 1000 can also becoupled to a second I/O bus 1150 via an I/O interface 1130. A pluralityof I/O devices may be coupled to I/O bus 1150, including a displaydevice 1124, an input device (e.g., an alphanumeric input device 1123and or a cursor control device 1122). The communication device 1121 isfor accessing other computers (servers or clients). The communicationdevice 1121 may comprise a modem, a network interface card, or otherwell-known interface device, such as those used for coupling toEthernet, token ring, or other types of networks.

Embodiments of the invention may include various steps as set forthabove. The steps may be embodied in machine-executable instructions. Theinstructions can be used to cause a general-purpose or special-purposeprocessor to perform certain steps. Alternatively, these steps may beperformed by specific hardware components that contain hardwired logicfor performing the steps, or by any combination of programmed computercomponents and custom hardware components.

Elements of the present invention may also be provided as amachine-readable medium for storing the machine-executable instructions.The machine-readable medium may include, but is not limited to, floppydiskettes, optical disks, CD-ROMs, and magneto-optical disks, ROMs,RAMs, EPROMs, EEPROMs, magnetic or optical cards, propagation media orother type of media/machine-readable medium suitable for storingelectronic instructions. For example, the present invention may bedownloaded as a computer program which may be transferred from a remotecomputer (e.g., a server) to a requesting computer (e.g., a client) byway of data signals embodied in a carrier wave or other propagationmedium via a communication link (e.g., a modem or network connection).

Whereas many alterations and modifications of the present invention willno doubt become apparent to a person of ordinary skill in the art afterhaving read the foregoing description, it is to be understood that anyparticular embodiment shown and described by way of illustration is inno way intended to be considered limiting. Therefore, references todetails of various embodiments are not intended to limit the scope ofthe claims, which in themselves recite only those features regarded asessential to the invention.

What is claimed is:
 1. A printing system that combines features of afirst bitmap image and features of a second bitmap image, the printingsystem comprising: a print engine; and a print controller operable for:receiving the first bitmap image as a background of a form, the bitmapimage including a plurality of printable features corresponding topositions of the bitmap image; receiving the second bitmap image asfill-in data to be filled in to the form, the second bitmap imageincluding a second plurality of printable features corresponding topositions of the bitmap image, wherein the second plurality of printablefeatures each have an assigned ink transparency; blending a feature ofthe first bitmap image with a corresponding feature of the second bitmapimage based on the assigned ink transparencies to form a blendedfeature; and combining the blended feature to form a blended image thatblends the first and the second bitmap images and is suitable forprinting.
 2. The printing system of claim 1, wherein blending comprisesadding a color value of a feature of the first bitmap image with a colorvalue of the corresponding feature of the second image, wherein thecolor value of the feature of one of the first and second bitmap imagesis scaled based on the assigned ink transparency.
 3. The printing systemof claim 2, wherein the scaled color value is the color value having thelowest value as between the color value of the printable feature of oneof the first bitmap image and the printable feature of the second bitmapimage.
 4. The printing system of claim 2, the print controller furtheroperable for adding a color value for the printable featureindependently for each color plane of the first bitmap image and thesecond bitmap image.
 5. The printing system of claim 4, the printcontroller further operable for combining the color values for eachcolor plane to obtain blended features.
 6. The printing system of claim1, wherein the plurality of printable features comprise picture elementsof a bitmap.
 7. The printing system of claim 1, wherein the printcontroller further operable for dividing the first and second bitmapimages into tiles, the tiles corresponding to areas of the bitmap imagesand wherein the printable features comprise the tiles.
 8. The printingsystem of claim 7, wherein combining the blended features comprisescombining the tiles.
 9. The printing system of claim 1, whereincorresponding first and second printable features have a color andwherein blending comprises: factoring the color of the correspondingsecond printable feature by the corresponding ink transparency; andcombining the factored color and the color of the first printablefeature to obtain a final color for the blended image.
 10. The printingsystem of claim 9, wherein the colors of the first and second printablefeatures have components in multiple color planes, the print controllerfurther operable for performing factoring and combining for each colorplane.
 11. The printing system of claim 10, wherein factoring furthercomprises factoring the color of the first printable feature and thecolor of the second printable feature by the ink transparency.
 12. Theprinting system of claim 11, wherein combining comprises adding thefactored color value to the greater of the color of the first and thecolor of the second printable feature.
 13. A non-transitorycomputer-readable medium tangibly embodying programmed instructionswhich, when executed by a computer system, are operable to execute amethod of combining features of a bitmap first image and features of asecond bitmap image, the method comprising: receiving the first bitmapimage as a background of a form, the bitmap image including a pluralityof printable features corresponding to positions of the bitmap image;receiving the second bitmap image as fill-in data to be filled in to theform, the second bitmap image including a second plurality of printablefeatures corresponding to positions of the bitmap image, wherein thesecond plurality of printable features each have an assigned inktransparency; blending a feature of the first bitmap image with acorresponding feature of the second bitmap image based on the assignedink transparencies to form a blended feature; and combining the blendedfeature to form a blended image that blends the first and the secondbitmap images and is suitable for printing.
 14. The computer-readablemedium of claim 13, wherein blending comprises adding a color value of afeature of the first bitmap image with a color value of thecorresponding feature of the second bitmap image, wherein the colorvalue of the feature of one of the first and second bitmap images isscaled based on the assigned ink transparency.
 15. The computer-readablemedium of claim 14, wherein the scaled color value is the color valuehaving the lowest value as between the color value of the printablefeature of one of the first bitmap image and the printable feature ofthe second bitmap image.
 16. The computer-readable of claim 14, whereinthe method further comprising dividing the first and second image intotiles, the tiles corresponding to areas of the images and wherein theprintable features comprise the tiles.
 17. A method of combiningfeatures of a first bitmap image and features of a bitmap second image,the method comprising: a print controller receiving the first bitmapimage as a background of a form, the bitmap image including a pluralityof printable features corresponding to positions of the bitmap image;the print controller receiving the second bitmap image as fill-in datato be filled in to the form, the second bitmap image including a secondplurality of printable features corresponding to positions of the bitmapimage, wherein the second plurality of printable features each have anassigned ink transparency; the print controller blending a feature ofthe first bitmap image with a corresponding feature of the second bitmapimage based on the assigned ink transparencies to form a blendedfeature; and the print controller combining the blended feature to forma blended image that blends the first and the second bitmap images andis suitable for printing.
 18. The method of claim 17, wherein blendingcomprises adding a color value of a feature of the first image with acolor value of the corresponding feature of the second bitmap image,wherein the color value of the feature of one of the first and secondbitmap images is scaled based on the assigned ink transparency.
 19. Themethod of claim 18, wherein blending comprises adding the color valuescaled based on the assigned ink transparency for the printable featurefor a black color plane only and adding color values independently ofink transparency for any other color planes of the first image and thesecond image.
 20. The method of claim 17, wherein corresponding firstand second printable features have a color and wherein blendingcomprises: factoring the color of the corresponding second printablefeature by the corresponding ink transparency; and combining thefactored colors to obtain a final color for the blended image.